The 90.degree. push out apparatuses used normally in glassware forming machines, particularly of the I.S. type, are well known in this art and usually comprise a horizontal hydraulic cylinder and piston assembly supported on a vertical rotary shaft. The piston rod of such assembly is provided with a plurality of article push-fingers and is moved inwardly and outwardly to extend the fingers to the dead plate located at the unloading station of the glassware forming machine. In this way the articles deposited on the dead arc trapped and then, by means of an adequated cam, the whole rotates to push out the glass articles from the dead plate and deposit them, at a predetermined velocity onto the unloading conveyor of the machine.
The velocity and movement control of this type of 90.degree. push-out for glassware forming machines, is determined exclusively by the design of the cam and its follower which rotate in synchronism with the velocity of the conveyor onto which the articles are received, in such way that the glass articles are pushed from the dead plate of the machine and deposited over the conveyor, at a velocity nearly equal-to the velocity of the conveyor, in order to avoid the falling and consequently breakage of the articles.
Even when such control mechanisms are functioning in a more or less efficient manner, it has not been possible to avoid a rather high percentage of breakage of the ware. This is because the cam profile is unalterable and operates with a cylinder type follower which is also unalterable. As a practical matter it is impossible to profile a cam exactly to the movement equation required for properly handling the various glass articles capable of being formed in a machine of this type. For example, in the case of round glass articles of large diameter, the unloading velocity may be deficient, because articles of relatively large width and low height are capable of traveling at considerable velocities and high accelerations compared to articles which are of greater relatively height and smaller diameter. Differently proportioned ware requires different cam and follower profiles and changing these items becomes expensive and time consuming.
The problem is even more critical when the ware is oval rather than cylindrical. Also, the thickness of the ware is of considerable importance, and the only way of handling such ware with the push out mechanism of prior art, is to deccelerate the machine motion and decrease production, since production at the same velocity of those which are more stable, would make the percentage of breakage absolutely unecomonical.
The movement control mechanisms for the 90.degree. push-out apparatus in the glassware forming machines of the prior art, therefore leaves much to be desired as to versatility, because they don't allow programming the production of the machine for different types of ware. It is necessary therefore using the prior art machines to engage in relatively long production of each type of ware.
The control cams of the prior art push-out apparatus, inherently are not versatile mechanisms and can be considered as designed for a single type of ware.
Consequently the long standing problem has prompted such variations as pantographic mechanisms to decrease or increase the accelerations caused by the push-out mechanism on the stationary ware until the present invention no really satisfactory improvement has been developed.